Unveiling dioxin dynamics: A whole-process simulation study of municipal solid waste incineration

Area of Science:

• Environmental Science
• Chemical Engineering
• Combustion Science

Background:

• Dioxin (DXN) formation during municipal solid waste incineration (MSWI) is theoretically understood but deviates from actual concentrations.
• Key factors influencing DXN deviation include MSW treatment type, waste characteristics, and operational controls.
• The precise progression of DXN generation, adsorption, and emission within MSWI processes, particularly concerning specific MSW components, lacks clarity.

Purpose of the Study:

• To develop a comprehensive numerical simulation model for the entire process of dioxin (DXN) concentration in a municipal solid waste incineration (MSWI) plant.
• To elucidate the evolution of DXN concentrations by simulating key stages from formation to emission.
• To provide a tool for developing strategies to reduce DXN emissions and advance intelligent control technologies.

Main Methods:

• A numerical simulation model was developed using FLIC and ASPEN software, integrating knowledge of MSW combustion and DXN mechanisms.
• The model incorporates six critical stages: precipitation/formation, high-temperature pyrolysis, high-temperature gas-phase synthesis, low-temperature catalytic synthesis, activated carbon adsorption, and atmospheric emission.
• Simulated experiments were conducted under benchmark and multiple operating conditions to validate the model's representation of DXN concentration evolution.

Main Results:

• The simulation model effectively represents the evolution of dioxin (DXN) concentrations throughout the municipal solid waste incineration (MSWI) process.
• Simulated experiments confirmed the model's accuracy under various operational conditions.
• The study successfully mapped the progression of DXN concentrations across the six simulated stages.

Conclusions:

• The developed numerical model provides a clear understanding of dioxin (DXN) concentration dynamics in municipal solid waste incineration (MSWI).
• This model serves as a foundation for creating effective strategies to minimize DXN emissions.
• The research supports innovation in intelligent control technologies for cleaner waste incineration.